This invention relates to swivel assemblies connecting a stationary installation in a body of water to a ship. One type of installation for transferring multiple products such as crude oil and treated crude oil, includes a long tower whose upper end can connect through hoses to a ship and whose lower end can connect to oil wells and to a controlling well head cellar with pumps and the like at the ocean floor. A swivel assembly at the top of such a tower, may have to transfer multiple cargoes and electrical power and signal currents between a rotary portion that rotates with a ship and a stationary portion that connects to the rest of the tower, and also to connect hydraulic lines, reinjectant gas lines, and the like between rotating and non-rotating portions thereof. Such an assembly requires a large number of seals which may require replacement at intervals. Access to different portions of the swivel assembly, without requiring removal of the entire massive assembly and disassembly thereof, is important in permitting on-site maintenance.